1. Field of the Invention
The present invention relates to router optimizations on the Internet, and more specifically to a system and method for improving the efficiency of routers on the Internet and/or cellular networks and/or other networks and alleviating bottlenecks and overloads on the network.
2. Background
With the current explosion of information transfer, optic fibers are becoming faster all the time. Most of the recent advances in the amounts of data that these fibers can carry per time unit have come from adding more and more wavelengths (termed lambdas) to the same fiber at the same time, a method which is called DWDM (Dense Wave Division Multiplexing). The biggest obstacle to this was the lack of suitable amplifiers, until the Erbium amplifiers were discovered in the late 80's, which have 2 advantages: 1. They don't need to convert the optical signals to electricity and back, but instead, light in the feeble input signals stimulates excited Erbium Atoms to emit more light at the same wavelength, 2. Because they preserve the wavelength of the optical signals, they can amplify many wavelengths simultaneously without having to first extract them separately and then recombine them after amplification. Typically a single optic fiber can carry today up to 80 different lambdas simultaneously, and the number is likely to increase further. As the Internet becomes more and more demanding for bandwidth, optic fibers will keep getting faster at a high rate. The upper limit for optic fibers using such methods is currently estimated to be around 100 terabits per second, and is expected to be achieved within the next 8 years.
However, the biggest bottleneck with such fibers today is the relatively much slower speed of the routers. There are two main methods for routing: circuit routing, and packet switching. In circuit routing, each connection gets a communication route for a certain time slice. This has typically been used until now mainly in telephony, but the big disadvantage is that typical data interactions have a peak 15 times greater than their average rate, so typically on average only 7% of the line is used. In packet switching the same route can be used by many users simultaneously, and the bandwidth is divided between the users by collecting bits together in packets (typically up to 64 Kilobytes per packet in the TCP/IP Internet protocol), and each packet has a header that contains among other things the target IP address of the packet. This way, the route can be utilized up to 100% instead of only 7%. Since the early 70's the computing cost to switch packets has been cheaper and has decreased at a faster rate than the communication speed cost, and this is the reason that the Internet started using packet switching. Today, packet switching is beginning to take over voice as well as data. According a thorough review, “ATM: Another technological mirage, or why ATM is not the solution” by Vadim Antonov, published in http://www.inetdevgrp.org/19980421/atm.htm, packet switching or something similar to it is needed not just for better utilization of the lines, but also because it is superior to circuit switching in many ways, such as better scaleability as the Internet grows, better handling of traffic congestions, and better routing flexibility. However, that article also shows that currently the system is incredibly complex and inefficient, with almost infinite router-tables updates having to propagate all the time. Another article, “Experts sound alarm on Internet Routing”, published on Light Reading on Nov. 1, 2000 at http://www.lightreading.com/document.asp?doc_id=2328, shows that the BPG tables (Border Gateway Protocols) are ballooning in size so fast that soon the entire system will crumble and definitely we will need to come up with new and better routing methods. Another thorough study, Middle Mile Mayhem, published by the Kellogg Graduate School of Management on the year 2000, at http://www.opnix.products_services/orbit1000/Middle_Mile_Mayhem.pdf, shows that billions of dollars per year are lost due to too slow and congested routers.
On the other hand, recently the ability of optic fibers to carry data has increased faster than the computing power, and the use of DWDM in optic fibers has resulted in routers separating between the lambdas in a way more similar to circuit switching. The start-up company Trellis Photonics for example created and patented a fast router that uses a special crystal that contains holograms and manipulates each lambda to into the wanted output fiber through the appropriate hologram by applying an electrical current to the crystal. Typically this switch has a response time of about 30 nanoseconds, which is among the fastest in the industry today, and can support optic fibers that carry even a few terabits per second (because the switching is done for large groups of bits, not for every bit of information that passes, and there can be time coordination on both sides for circuit switching), and Trellis will probably have soon faster switches with a few nanoseconds response time. Another start-up company—Lynx—claims that it will soon have a faster router that uses, instead of holograms, Lithium Niobate waveguides, which will typically have a response time of about 4-5 nanoseconds.
Even with DWDM, Packet switching is of course still used on the Internet after separating the lambdas, but the biggest problem with packet switching is that the computation requirements for analyzing the packets, finding their target IP addresses, looking them up in the database, and determining their required destination routes, create a severe bottleneck and slow down the process considerably. Translating the information from the light bits into electronic bits for processing in electronic computers and then translating it back to light bits is too much time-consuming. For this reason, there are today a number of companies and university departments who are trying to work in the direction of all-optical switches, which will be able to analyze the information within the data packets directly in the form of light bits, or various hybrid systems that will combine electronics and photonics. According to the thorough review “Technology: Optical illusions?”, published in http://www.americasnetwork.com/issues/2000issues/20000901/20000901_optical.html, the idea of reading the header separately without disrupting the optical bit stream and using that information to send a control signal to an optical switch has been already suggested in numerous research papers in various scientific journals, starting from the early 90's, but the biggest problems have been the speed of the switching element, and the buffering of the packets. Another good review of such problems is “Advances in Photonic Packet Switching: An overview”, by Yao et. al., published in IEEE Communications Journal on February 2000, describing for example various complex attempts to synchronize the packets.